The word(s) "disbelieve" appears 631 time(s) in 561 verse(s) in Quran in Mohsin Khan translation.

(331) And indeed We sent Nuh (Noah) to his people, and he stayed among them a thousand years less fifty years [inviting them to believe in the Oneness of Allah (Monotheism), and discard the false gods and other deities]; and the Deluge overtook them while they were Zalimun (wrong-doers, polytheists, disbelievers).

(332) And those who disbelieve in the Ayat (proofs, evidence, verses, lessons, signs, revelations, etc.) of Allah and the Meeting with Him, it is they who have no hope of My Mercy: and it is they who will have a painful torment.

(333) And thus We have sent down the Book (i.e. this Qur'an) to you (O Muhammad صلى الله عليه وسلم), and those whom We gave the Scripture [the Taurat (Torah) and the Injeel (Gospel) aforetime] believe therein as also do some of these (who are present with you now like 'Abdullah bin Salam) and none but the disbelievers reject Our Ayat [(proofs, signs, verses, lessons, etc.,) and deny Our Oneness of Lordship and Our Oneness of worship and Our Oneness of Our Names and Qualities: i.e. Islamic Monotheism].

(334) Say (to them O Muhammad صلى الله عليه وسلم): "Sufficient is Allah for a witness between me and you. He knows what is in the heavens and on earth." And those who believe in Batil (all false deities other than Allah), and disbelieve in Allah and (in His Oneness), it is they who are the losers.

(335) They ask you to hasten on the torment. And verily, Hell, of a surety, will encompass the disbelievers.

(336) And if you were to ask them: "Who has created the heavens and the earth and subjected the sun and the moon?" they will surely reply: "Allah." How then are they deviating (as polytheists and disbelievers)?

(337) And who does more wrong than he who invents a lie against Allah or denies the truth (Muhammad صلى الله عليه وسلم and his doctrine of Islamic Monotheism and this Qur'an), when it comes to him? Is there not a dwelling in Hell for disbelievers (in the Oneness of Allah and in His Messenger Muhammad صلى الله عليه وسلم)?

(338) And on the Day when the Hour will be established, the Mujrimun (disbelievers, sinners, criminals, polytheists) will be plunged into destruction with (deep regrets, sorrows, and) despair.

(339) And on the Day when the Hour will be established - that Day shall (all men) be separated (i.e. the believers will be separated from the disbelievers).

(340) And as for those who disbelieved and belied Our Ayat (proofs, evidence, verses, lessons, signs, revelations, Allah's Messengers, Resurrection, etc.), and the Meeting of the Hereafter, such shall be brought forth to the torment (in the Hell-fire).